CLINICO-EPIDEMIOLOGICAL ALGORITHM FOR PREDICTING SYSTEMIC ARTERIAL HYPERTENSION AT HIGH ALTITUDE THROUGH MATHEMATICAL MODELLING

A population based hybrid design combining element of cohort and cross-sectional approach was used to develop a simple clinical algorithm to predict individual probability of developing hypertension (systolic BP > 140 mm Hg and/or diastolic BP > 90 mmHg). 3615 soldiers initially normotensive at the time of induction into high altitude, were studied by systematic random sampling. Multiple logistic regression analysis showed a high significant association between hypertension and age, body mass index (BMI), tobacco smoking and alcohol consumption. Using the constant/coefficient values obtained from the logistic model and the receiver operating characteristics (ROC) curve analysis, the following predictive rule was developed – To the age in years, add (BMIx 3.86); also add 5.53 if he is a smoker; and add 19.81 if he consumes alcohol. If the total exceeds 142, the individual is at high risk of developing hypertension. This algorithm carries a sensitivity of 68.2% and specificity of 78.5%.KEY WORDS: Hypertension, High altitude     

A SEARCH FOR UNHAPPY ABDOMEN: PREVALENCE OF IRRITABLE BOWEL SYNDROME IN GENERAL POPULATION

The irritable bowel syndrome is the commonest gastrointestinal disorder seen in practice but its exact prevalence in India is not known. This study was carried out to determine the prevalence of symptoms compatible with this diagnosis in general population. A cross sectional random sample survey was conducted in various strata of urban population in Wanoworie area of Pune. Survey utilized personal interviews based on a questionnaire. Symptoms were evaluated as per Manning criteria and the diagnosis of irritable bowel syndrome was defined by Kruis diagnostic index. Of the 1010 subjects interviewed, 370 (37%) reported more than 6 episodes of abdominal pain in previous 6 months, with 333 reporting symptoms consistent with the the diagnosis of irritable bowel syndrome. At least one of the Manning''s symptoms was present in 307 out of 370 subjects (83%). The male female ratio was 5.3:1. Among males, 288 (35%) and among females 82 (53.2%) persons had at least some degree of abdominal discomfort. Other common symptoms were: excessive passage of wind (42.2%), irregular bowel habits (33%), excessive belching (30.8%), constipation (27.5) and feeling of incomplete evacuation(28.1%). About one third of the symptomatic subjects (134 or 36.2%) had seen a doctor or wanted to be seen by a specialist. Overall prevalence of the symptoms consistent with irritable bowel syndrome thus, is 33 per cent though only about a third of these may possibly consult a doctor. Follow up of all these patients for a mean duration of 8.3 months showed that no case of organic disease was picked up either by the scoring system or by the gastroenterologist. Symptoms consistent with the diagnosis of irritable bowel syndrome are see in almost one third of the study population residing in Wanoworie area of Pune.KEYWORDS: Irritable bowel syndrome, Kruis diagnostic index, Manning''s symptoms     

A BEFORE AND AFTER TRIAL OF THE EFFECTIVENESS OF NETWORK ANALYSIS IN HEALTH OPERATIONS MANAGEMENT

An intervention trial using “before-and-after” approach was undertaken to address the question whether network analysis as a health managerial tool of control can favourably affect the delays that occur in planning and executing the antimalaria operations of a Station Health Organization in a large military station. Exposure variable of interest was intervention with a network diagram, by which the potential causes of delay along the various activities were assessed and remedial measures were introduced during the second year. Sample size was calculated using conventional alpha and beta error levels. The study indicated that there was a definite beneficial outcome in that the operations could be started as well as completed in time during the intervention year. There was reduction in time requirement in 5 out of the 9 activities, the exact ‘p’ value being 0.08, by both parametric and non-parametric tests. The use of network analysis in health care management has been recommended.KEY WORDS: Health services research, Health care, Health plan implementation, Malaria, Network analysis, Operations research     

APPLICATION OF HAZARD ANALYSIS CRITICAL CONTROL POINT SYSTEM : ANALYSIS OF A FOOD POISONING OUTBREAK

The World Health Organization as well as several experts have recently recommended the use of hazard analysis critical control point system for prevention of food-borne illnesses. The present study proceeded to identify the hazardous operations and their critical control points by investigating, through a case-control design, an outbreak of food poisoning. The predominant presenting symptoms were watery diarrhoea and abdominal cramps. The cumulative incidence during this episode was 28.6 per cent, with a median incubation of 13 hours. Evaluation of food histories indicated a very high and significant odds ratio for mutton dish (OR = 6.45; p < 0.001), which persisted even after adjusting for the consumption of other food items through stratified analysis using the Mantel-Haenszel procedure. Environmental assessment revealed a strong possibility of contamination of raw mutton at the source with animal excreta and prolonged storage at room temperature of cooked mutton dish. Based on these findings, hazardous operations were identified and critical control points and monitoring criteria for prevention of food poisoning have been suggested.KEY WORDS: Food poisoning, Epidemiologic methods, Hazard analysis critical control point (HACCP)     

EPIDEMIOLOGICAL STUDY OF ENTEROPATHOGENIC CARRIER STATE AMONG FOOD HANDLERS OF ARMED FORCES EATING ESTABLISHMENTS

A cross-sectional epidemiological study was undertaken on a randomly selected sample of 308 food handlers working in different eating establishments of Indian Armed Forces in Pune. These included 101 Service personnel and 207 civilians. Stool samples were analysed for enteropathogens and epidemiological assessment of gastrointestinal disease occurrence in the military units of these food handlers was undertaken. The study revealed that 4 of the subjects were carriers of salmonella typhimurium, thus giving the prevalence as 1.3% (95% confidence interval 0.2% to 2.56%). No other enteropathogen except salmonella typhimurium was isolated. The positive carriers showed a typical “spatial - clustering” in that they were working in two geographically contiguous medical units.KEY WORDS: Carriers, Food-handlers, Salmonella typhimurium     

A MATHEMATICAL MODEL FOR PREDICTING THE PERSISTENCE AND EFFICACY OF BACILLUS THURINGIENSIS VAR ISRAELENSIS IN RELATION TO WATER POLLUTION

In a simulated field trial, the bead formulation of Bacillus thuringiensis var israelensis (Bti) was found to be more persistent in moderately polluted as compared to highly polluted water. A mathematical model was built up to study the influence of time (independent variable) on larval reduction (dependent variable) in relation to degree of water pollution. Two predictive models for different grades of water pollution were developed, which estimated that the larval mortality in moderately polluted water was likely to decline by 3.79 as compared to 5.02 on an average, in highly polluted water with each passing day.KEYWORDS: Biocide, Mosquito control, Prediction model     

CROSS SECTIONAL ANALYTIC STUDY OF AWARENESS REGARDING FACTORS RELATED TO CHILD SURVIVAL AMONG MARRIED WOMEN IN A SEMI-URBAN COMMUNITY

A cross sectional analytic study was undertaken on 480 married women living in a semi-urban locality in Pune, with the objective of assessing their awareness regarding factors related to child survival. It was observed that 62.1 per cent of the ladies had adequate knowledge about immunisation. A highly significant trend was evident as regards knowledge about immunisation and formal education and socio-economic status (p<0.01). 93 per cent ladies initiated breast feeding within 24 hours of birth of the new born. Significantly larger proportion of ladies from lower education favoured prolonged breast feeding (p<0.001) and favoured late introduction of top milk (p<0.001). In general, the awareness about growth chart was very poor with only 3.5 per cent ladies having adequate knowledge. Larger family size was significantly associated with declining probability of use of oral rehydration solution (ORS). Certain recommendations for improving the awareness regarding child survival have been submitted accordingly.KEYWORDS: Child survival, Health awareness     

A STUDY OF METHODS USED FOR DISINFECTION OF ANAESTHETIC EQUIPMENT BETWEEN TWO SURGICAL OPERATIONS AT A LARGE TEACHING HOSPITAL

A prospective study on the growth of bacteria on certain commonly used anaesthetic equipment was undertaken in a large teaching hospital with a view to assess the effectiveness of disinfection/sterilization procedures. Samples for microbiological assessment were drawn by the worker using standardised procedures and tested in the laboratory by a microbiologist, blinded to the type of sample. Criteria for growth positivity was taken as > 25 colony forming units. A total of 90 observations were taken. 30 each for ’before use’, ’after use’ and ’after disinfection’. Overall 54.6% of the equipment showed growth “before use” with maximum growth being seen in Suction catheters (66.6%) and Guedal airways (60.0%). On the other hand, the proportion of equipment showing growth “after use” was quite high (84.6%), with suction catheters and endotracheal tubes showing 90.0% growth each. There was significant difference as regards “before” and “after” use growth on Endotracheal tubes, Guedel airways and Face masks (p < 0.05). Analysis of growth “after” disinfection” revealed that the probability of growth remains as high as 70% in suction catheters (95% CI=54% to 86%) and 60% in laryngoscopes (95% CI=43% to 78%). The study revealed gross inadequacies in methods of disinfection being followed at present.KEY WORDS: Anaesthetic equipment, Disinfection     

EFFECTIVENESS OF A HEALTH EDUCATIONAL PACKAGE FOR AIDS PREVENTION AMONG ADOLESCENT SCHOOL CHILDREN

A randomised, controlled, community based intervention trial was undertaken to assess the effectiveness of a Health Education Programme (HEP) for HIV infection and AIDS among school children at Pune. Sample size was calculated on the basis of conventional Type I and Type II errors. School children studying in classes 9th to 12th in six different schools (n=1102) formed the study material. Baseline assessment for knowledge for AIDS/HIV was undertaken and used for formulating the Health education Programme Package. Randomisation was done so as to allocate five schools into trial group (n=803) and one school into control group (n=299). Blinding was also ensured to reduce bias. The study revealed that the HEP was very effective in improving the knowledge, the difference being highly significant as compared to control group. The effect was specially well marked for girls in school level (OR=4.76) followed by boys intermediate level (OR=3.11); there was clear evidence of statistical effect modification as regards this ‘sex and educational class’ differential (Woolfs''chi square=11.82, p < 0.0001). The study also revealed that the maximum aceceptability of programme was among girls studying in girls school (Stratum OR =2.25) followed by boys in boys school (OR=1.50) compared to students in co-educational system (linear trend chi square=9.35, p < 0.01). Certain recommendations for health education for HIV/AIDS among school children have been submitted.KEY WORDS: AIDS, Health education, Randomised controlled trial